Anamorphic three-perforation imaging system

ABSTRACT

An anamorphic imaging system is disclosed which maximizes the use of available image area to minimize display magnification and image degradation due to display magnification, reduces the amount of anamorphic squeeze or stretch during photography to lower image degradation due to anamorphosis, and in film applications, utilizes a film frame that is only three perforations in height to reduce the amount of original film needed. The frame for either film or digital applications has an aspect ratio of approximately 16:9, is contained within the total available frame area of a three-perforation frame or digital imager, and is sized to maximize image area. In preferred embodiments, the image capture area is approximately 0.900 inches wide by approximately 0.506 inches tall.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-In-Part (CIP) of U.S. applicationSer. No. 10/927,731 entitled “Anamorphic Three-Perforation ImagingSystem” filed on Aug. 27, 2004 now U.S. Pat. No. 7,148,947, which claimspriority to U.S. Provisional Application No. 60/560,800 filed on Apr. 7,2004, entitled “Anamorphic Three-Perforation Imaging System,” and isrelated to U.S. Utility application Ser. No. 10/923,289 filed on Aug.20, 2004, entitled “Anamorphic Imaging System,” the contents of whichare incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, generally, to the optimization of imagequality when the aspect ratio of the acquisition format is a generallyrecognized standard and the display aspect ratio is represented by adifferent but also generally recognized standard.

2. Description of Related Art

In the early 1950s, as a result of the perceived threat of television,motion pictures began to be released in various widescreen formats.Until this time the majority of feature films and television programswere released with frames having an aspect ratio of 1.33:1 (4:3).Although numerous widescreen formats were introduced in the 1950s, onlya cropped version of the 1.33:1 aspect ratio commonly known as 1.85(1.85:1 aspect ratio with dimensions of 0.825 inches by 0.446 inches)and Panavision®, an anamorphic optical system with a 2:1 horizontalsqueeze and a 2.40:1 aspect ratio (0.825 inches by 0.690 inches),survive today as release print formats.

The Panavision® Anamorphic Format

The Panavision® anamorphic 2.40:1 widescreen system is generallypreferred for major motion pictures because of its superior screen imagequality. Panavision® was an improvement to an earlier anamorphic systemintroduced by 20^(th) Century Fox as Cinemascope®, which used ananamorphic lens to squeeze the optical image onto the available filmframe during filming. (Anamorphic lenses are essentially astigmatic; themagnification in the horizontal direction is different from themagnification in the vertical direction.)

FIG. 1 illustrates the SMPTE 195-2000 projection aperture standard for afilm frame generated using the Panavision® anamorphic format. Area 100is the full camera aperture, but area 102 (having an aspect ratio ofapproximately 1.2:1) is the portion of the film frame that is actuallyprojected. The optical image in area 102 has been squeezed in a 2:1ratio, and thus exemplary image 104, although appearing as an oval, isactually a circular image that has been photographed.

The original film may then be converted directly to release print filmwithout changing or otherwise manipulating the format of FIG. 1. Whenprojecting the release print film, another anamorphic projectionattachment is used to unsqueeze the image. When unsqueezed duringprojection, area 102 will have an aspect ratio of approximately 2.40:1,and the oval exemplary image 104 will return to its correct circularshape.

Anamorphosis is typically employed to maximize the available image areaon the film frame. The standard Panavision® anamorphic projectionaperture is 0.825 inches×0.690 inches, resulting in an image area of0.569 square inches. (See FIG. 1, also the SMPTE Standard). Whencompared to the 1.85:1 spherical widescreen format 0.825×0.446 with anarea of approximately 0.368 square inches, the Panavision® anamorphicformat has 55% more film area. In general, anamorphic optics areinferior to their spherical counterparts, and produce a degraded image.The greater the amount of anamorphosis (squeezing or stretching), thegreater the degree of image degradation. Nevertheless, the Panavision®anamorphic format produces improved overall image quality because theincreased image area reduces the amount of magnification needed toproject the image on a theatre screen, as compared to the 1.85:1spherical format. For example, to project an image that is 15 feet tall(as in a conventional movie theater), the Panavision® anamorphic formatrequires a 261× image magnification in the vertical direction, while the1.85:1 format requires a 404× image magnification in the verticaldirection. There is a direct correlation between magnification and imagedegradation, when viewed from the same distance. Because of the largermagnification required by the 1.85:1 format, film grain, dust or otherimperfections in the film frame would appear much larger when projectedin the 1.85:1 format as compared to the Panavision® anamorphic format.

It should be noted that the Panavision® frame of FIG. 1 is off-centeredto leave area 106 for an optical soundtrack. This technique ofgenerating an off-centered, right-shifted frame (a.k.a. “Academy frame”)was developed because historically, the original film would be put incontact with another piece of film and the soundtrack would be recordedoptically onto that piece of film to generate the release print film.Even today, this optical soundtrack is needed on release print film.Therefore, original film is still frequently shot “Academy centered” toleave room for the optically recorded soundtrack and other digitalsoundtracks.

FIG. 1 illustrates perforations 108 along either side of the film, usedby pull-down mechanisms within cameras for advancing the film. The vastmajority of film cameras and projectors use a mechanism for pulling downfour perforations per frame, and thus the Panavision® frame illustratedin FIG. 1 has a height that spans four perforations.

Three-Perforation Formats that Preserve the Optical Soundtrack DuringCapture

U.S. Pat. No. 3,865,738 entitled “Method of Making Motion Pictures”issued to Miklos Lente on Feb. 11, 1975 (hereinafter “the Lente patent”)describes a system using 35 mm frames three perforations in height forthe purpose of saving original film. This savings would not apply totheatrical release print film, however, because the Lente patent systemenvisioned converting the original film to release print film, with itsstandard four perforations per frame.

The Lente patent envisioned capturing Academy centered images with ahorizontal squeeze on the original film within a three perforationframe, with the optical soundtrack preserved at the left edge of theframe (see FIG. 6 of the Lente patent). This original film would then beconverted to conventional print film with four perforations per frame(see FIG. 8 of the Lente patent) by stretching the image optically inthe vertical direction using an optical printer on an optical bench. Theconventional print film could then be used on conventional projectorswith 2:1 anamorphic projection attachments with mechanisms for pullingdown four perforations per frame. Again, the image area of the originalnegatives extracted for projection would be much smaller than thestandard Panavision® anamorphic projection aperture. The image would bedegraded by its extraction for projection conversion to release printfilm using an optical printer, and additional magnification neededduring projection due to the smaller negative image area, and thereforewould be of inferior quality as compared to the Panavision® anamorphicformat.

Lente also authored “The Proposed Trilent-35 System” in the June 1976issue of American Cinematographer (hereinafter “the Lente article”). TheLente article disclosed a system similar to the Lente patent which wouldhave the same image quality limitations (see FIGS. 7 and 8 in such Lentearticle).

35 mm negatives with only three perforations per frame was alsodisclosed in “Three-Perf in the Future” by Rune Ericson in the July 1986edition of American Cinematographer (hereinafter “Ericson”). Ericsonproposed the use of three perforation frames for both original film andrelease prints in order to save on film costs. Ericson envisioned animage area within a three perforation frame and with the opticalsoundtrack preserved at the left edge of the frame for obtaining printframes with a 1.85:1 aspect ratio without the use of anamorphosis duringfilming. However, the three-perforation high release prints wouldrequire three-perforation projectors that were never adopted by themotion picture industry. Because the original film would be shot using aspherical lens and would not need to be converted using an opticalprinter, the image degradation that would result from the use of ananamorphic lens during filming and conversion to release print film onan optical printer would be avoided. Note, however, that the image areaof this embodiment of Ericson would be smaller than the standardPanavision® anamorphic projection aperture of 0.569 square inches. Thus,although the image would not be degraded by anamorphosis during filmingor during conversion on an optical printer, the overall image qualitywould be inferior as compared to the Panavision® anamorphic format dueto the need for increased magnification during projection.

Three-Perforation Formats that Eliminate the Optical Soundtrack DuringCapture

As noted above, most original film is still shot off-centered to leaveroom for the optically recorded soundtrack and other digital tracks.While practical, this practice is wasteful of film area, and is notabsolutely necessary, because the images can be Academy-centered whenthe negative film is converted to release print film. Because of thehigh cost of negative film, suggestions have previously been made forusing the area reserved for the soundtrack during filming by extendingthe width of the frame from perforation to perforation (a.k.a.“film-centered”). Of course, the negative film must still be convertedto Academy centered release print film.

Additionally, because of the high cost of original film negatives,suggestions have previously been made for reducing the height of a framefrom four perforations to three perforations and removing the areareserved for soundtrack. For example, in “A Universal Format for FilmProduction” by N. D. Bernstein, M. Z. Wysotsky and B. N. Konoplev in theSeptember 1973 Journal of the SMPTE, Vol. 82 (hereinafter “Bernstein”),35 mm negatives with only three perforations per frame were disclosed(see FIG. 2). By pulling down three perforations per frame instead offour, a 25% savings in original film could be realized. This savingswould not apply to release print film, however, because Bernsteinenvisioned converting the original film to release print film with thestandard four perforations per frame.

Bernstein and Ericson both envisioned a widescreen image area within thethree perforation frame (see FIG. 2) that did not leave room for theoptical soundtrack at the left edge of the frame for obtaining printframes with aspect ratios of 2.35:1 (today 2.40:1). Bernstein andEricson both teach that no anamorphosis would be required duringfilming. Bernstein teaches, and Ericson mentions that as an alternative,the original film would have to be converted using an optical printer toa four perforation anamorphic internegative with an area at the leftedge of the frame for the optical soundtrack, per FIG. 1, area 106. Thisconversion would require two operations, either squeezing in thehorizontal direction and magnifying the image or alternativelystretching in the vertical direction and minifying the image, eachoperation contributing to image degradation. Note also that the imagearea of this embodiment of Bernstein would be only 0.412 square inchesas compared to the standard Panavision® anamorphic camera aperture of0.638 square inches (0.868″×0.735″). The image would therefore bedegraded by both the anamorphic conversion to release print film and theincreased magnification needed during projection, and therefore be ofinferior quality when compared to the Panavision® anamorphic format. InEricson, no anamorphosis would be required during filming or conversionto release prints, because Ericson envisioned release prints in threeperforation having an aspect ratio of 2.35:1 today (2.40:1) withoutsound. Note that the image area of this embodiment of Ericson would alsobe smaller than the standard Panavision® anamorphic projection aperture.The image would therefore be degraded by the increased magnificationneeded during projection, and would be of inferior quality as comparedto the Panavision® anamorphic format.

FIG. 2 illustrates a frame 200 of a film format known as “Super 35,”having an aspect ratio of 2.40:1, today's anamorphic projection format,which was introduced to reduce the cost of 2.40:1 anamorphic originalphotography. Consistent with the Bernstein and Ericson proposals, thisnew format also utilizes a camera aperture that is contained withinthree perforations rather than the traditional 35 mm film frame that isfour perforations in height. No anamorphosis is required during filming,as evidenced by the exemplary image 202, which appears as its correctcircular shape on the film. The original film must still be converted torelease print film having an area at the left edge of the frame for theoptical soundtrack by squeezing in the horizontal direction orstretching in the vertical direction, and then either magnifying orminifying the image, but modern digital processes enable this conversionto occur without the degradation in image quality that would normallyoccur if the conversion was effected using an optical printer. Themotion picture “Panic Room,” for example, was filmed in threeperforation Super 35 with an aspect ratio as shown in FIG. 2, and wasdigitally converted to the format of FIG. 1. The process of filming inSuper35 with an aspect ratio of 2.40:1 was used to eliminate thedistortion created by squeezing during filming. Note, however, that theimage area of this embodiment is only 0.372 square inches when comparedto the standard Panavision® anamorphic projection aperture of 0.569square inches. Thus, although there is no image degradation duringfilming or during the conversion to release print film from Super 35,the image is nevertheless degraded by the increased magnification neededduring projection.

The processes described above focused on reducing original negative filmused in filming by using three perforation film frames rather than four.Some of these processes eliminated one or more of the contributors toimage quality degradation by either eliminating anamorphosis duringfilming or eliminating the need for conversion to release print filmusing an optical printer. However they were unable to optimize theresulting image because they were unable to use the whole availableimage area (thereby increasing the amount of magnification needed duringprojection). Thus, a need exists for an anamorphic imaging system thatmaximizes image quality by maximizing the image area of the originalnegative film, thereby decreasing the amount of magnification neededduring projection, while at the same time saving original negative film.

SUMMARY OF THE INVENTION

An anamorphic imaging system according to embodiments of the presentinvention utilizes a maximized image capture area in either cine ordigital applications to reduce magnification and image degradation dueto magnification when displayed, and to reduce the amount of anamorphicsqueeze or stretch during photography to lower image degradation due toanamorphosis. The amount of horizontal anamorphic squeeze (for frontanamorphs) or vertical anamorphic stretch (for rear anamorphs) usedduring widescreen photography is, for example, in the ratio of 2.40:1over 16:9 or approximately 1.34 to maximize the image capture area.Alternatively, the amount of vertical anamorphic squeeze (for frontanamorphs) or horizontal anamorphic stretch (for rear anamorphs) usedduring standard television (1.33:1 aspect ratio) photography is in theratio of 16:9 over 1.33:1, which is also approximately 1.34. Note thanan anamorphic squeeze or stretch other than this ratio will not maximizethe image capture area and thus will not maximize overall image quality.

In film applications, the present invention utilizes a film frame thatis only three perforations in height to reduce the amount of originalfilm needed. The total available frame area in a three perforation highfilm frame is approximately 0.980 inches by 0.546 inches. Embodiments ofthe present invention capture images in a frame with an aspect ratio of16:9, contained within the total available frame area and sized tomaximize image area. A widescreen image (2.40:1) may be captured usingan anamorphic lens with a horizontal squeeze ratio of approximately1.34, chosen to horizontally squeeze the widescreen image to the size ofthe frame while maximizing the image capture area. In addition, awidescreen image may be captured using a rear anamorphic lens with avertical stretch ratio of approximately 1.34, chosen to verticallystretch the widescreen image to the size of the frame, as described inrelated U.S. Utility application Ser. No. 10/923,289 entitled“Anamorphic Imaging System.” Alternatively, a standard television imagemay be captured using an anamorphic lens with a vertical squeeze ratioof approximately 1.34, chosen to vertically squeeze the standardtelevision image down to the size of the frame while maximizing theimage capture area. In addition, the standard television image may becaptured using a rear anamorphic lens with a horizontal stretch ratio ofapproximately 1.34, chosen to horizontally stretch the standardtelevision image to the size of the frame, as described in related U.S.Utility application Ser. No. 10/923,289 entitled “Anamorphic ImagingSystem.” Note that the same anamorphic lens with a 1.34 squeeze orstretch ratio, rotated 90 degrees, may be utilized to capture bothformats on the same image capture area.

Additionally, the frame may be sized in consideration of digital imagersused for cine applications. Digital imagers may be employed forcapturing images for standard television, digital television and motionpictures. Because of the international adoption of 16:9 (1.78:1) as adigital television aspect ratio, digital imaging systems for televisionand electronic cinematography are being designed to have an aspect ratioof 16:9. In addition, digital imagers for electronic cinematographyapplications are being designed with a size that approximates the areaof three-perforation film as described above. As with film, embodimentsof the present invention seek to maximize the active area of a digitalimager by capturing a widescreen or standard television image using ananamorphic lens with a horizontal or vertical squeeze of approximately1.34, respectively.

Preferred embodiments of the present invention therefore employ an imagecapture area with dimensions selected in consideration of multiplefactors, some applicable to both film and digital applications, and somespecific to either film or digital applications. The image capture areais selected to maximize the image area to reduce magnification and imagedegradation due to magnification, and reduce the amount of anamorphicsqueeze or stretch during filming to lower image degradation due toanamorphosis. Use of a single image capture area also enables the sameanamorphic lenses to be used for both film and digital capture. Theimage capture area is further selected to be only three perforations inheight to reduce the amount of original film needed for filmapplications, and to fit within the maximum three perforation high imagearea of approximately 0.980 inches by 0.546 inches. The image capturearea is still further selected to have an aspect ratio of 16:9 fordigital television, and to fit within the total imaging area of adigital imager of approximately 0.945 inches by 0.532 inches.

The image capture area of preferred embodiments of the present inventionis approximately 0.900 inches wide by approximately 0.506 inches tall,providing an aspect ratio of approximately 16:9. The image capture areafits within the total available film area of a three perforation filmframe and the total imaging area of a digital imager.

For both film and digital applications, either widescreen or standardtelevision images may be captured using the same anamorphic lens havingan approximate 1.34:1 horizontal or vertical squeeze or stretch (rotated90 degrees as needed), which is less than the 2:1 horizontal squeeze ofthe Panavision® anamorphic format. The reduced degree of anamorphosiscombined with using practically the entire area of the three perforationfilm frame or total digital imaging area results in a screen imagequality that is at least equivalent, and potentially superior to, thePanavision® anamorphic format, while still providing an approximate 25%film cost savings over the conventional four perforation format.

With regard to widescreen images, embodiments of the present inventionutilize known digital processing techniques implemented by digital imageprocessors to convert the original negative film or captured digitalimage to the format of FIG. 1, which avoids the additional degradationthat would occur with the use of an optical printer lens.

In one embodiment of the present invention, a widescreen image capturedon original film according to embodiments of the present invention maybe digitally stretched vertically and then digitally resampled such thatthe resulting film print has the format of FIG. 1. In preferredembodiments, the original image is stretched by about 49% in thevertical direction. Alternatively, in another preferred embodiment ofthe present invention, the widescreen image on the original film isdigitally squeezed horizontally and then digitally resampled such thatthe resulting film print has the format of FIG. 1. In this preferredembodiment, the original image is squeezed by about 49% in thehorizontal direction. An anamorphic projection attachment with a 2:1horizontal unsqueeze may then be used to project the release print filmand produce the final 2.40:1 projected image.

In another embodiment of the present invention, a widescreen imagecaptured on a digital detector sized according to embodiments of thepresent invention (i.e., having an aspect ratio of about 1.78:1) may bemagnified or minified as needed, but without further stretching orsqueezing, to fit into the display area of the projection chip incurrent state of the art digital cinema projectors, which may have anaspect ratio of about 1.9:1. In this embodiment, a minimal amount of thewidth of the projection chip will not be used. An anamorphic projectionattachment with a 1.34:1 horizontal unsqueeze may then be used toproject the 1.78:1 aspect ratio captured image and produce the final2.40:1 projected image. Alternatively, the captured widescreen image maybe converted using digital processing techniques (magnifying, minifying,stretching or squeezing as needed) implemented by digital imageprocessors to precisely fit the 1.9:1 aspect ratio projection chip. Ananamorphic projection attachment with a 1.26:1 horizontal unsqueeze maythen be used to project the 1.9:1 aspect ratio digital image and producethe final 2.40:1 projected image. Note that digital cinema projectorswith other aspect ratios may also be supported simply by changing thedigital processing and anamorphic projection of the captured image.

In another embodiment of the present invention, a widescreen imagecaptured on a digital detector sized according to embodiments of thepresent invention may be digitally stretched horizontally by about 34%or digitally squeezed vertically by about 34% to restore the 2.40:1aspect ratio, then digitally processed as needed for use in digitalapplications (digital television, LCD screens on cameras and camcorders,etc.).

In another embodiment of the present invention, a standard televisionimage captured on a digital detector sized according to embodiments ofthe present invention may be converted using digital processingtechniques to an image with an aspect ratio of about 1.9:1, which may bethe aspect ratio of current state-of-the-art DLP projectors, and thenoptionally digitally magnified or minified to fit the actual projectionarea of the DLP projector. An anamorphic projection attachment with a1.43:1 vertical unsqueeze may then be used to project the 1.9:1 aspectratio digital image and produce the final 4:3 projected image. Note thatDLP projectors with other aspect ratios may also be supported simply bychanging the digital processing and anamorphic projection of thecaptured image.

In another embodiment of the present invention, a standard televisionimage captured on a digital detector may be digitally stretchedvertically by about 34% or digitally squeezed horizontally by about 34%to restore the 2.40:1 aspect ratio, then digitally processed as neededfor use in digital applications (digital television, LCD screens oncameras and camcorders, etc.).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example original film frame generated using thePanavision® anamorphic format.

FIG. 2 illustrates a frame of a film format known as “Super 35,” wasintroduced to reduce the cost of shooting in the anamorphic format or2.40:1 anamorphic original negative film for conversion and release in a2.40:1 aspect ratio, per FIG. 1.

FIG. 3 illustrates an exemplary three perforation anamorphic film frameproduced by an anamorphic imaging system according to embodiments of thepresent invention.

FIG. 4 illustrates an exemplary digital imager capable of capturing adigital image produced by the anamorphic imaging system according toembodiments of the present invention.

FIG. 5 illustrates one exemplary process for converting a widescreenimage captured according to embodiments of the present invention intothe final or release print image.

FIG. 6 illustrates another exemplary process for converting a widescreenimage captured according to embodiments of the present invention intothe final or release print image.

FIG. 7 is an illustration that summarizes the capture of a widescreenimage on a digital detector according to embodiments of the presentinvention, its use in a portion of a projection chip and its subsequentprojection using a digital cinema projector.

FIG. 8 is an illustration that summarizes the capture of a widescreenimage on a digital detector according to embodiments of the presentinvention, its use in the full area of a projection chip and itssubsequent projection using a digital cinema projector.

FIG. 9 is an illustration that summarizes the capture of a standardtelevision image on a digital detector according to embodiments of thepresent invention, its use in a portion of a projection chip and itssubsequent projection using a digital cinema projector.

FIG. 10 is an illustration that summarizes the capture of a standardtelevision image on a digital detector according to embodiments of thepresent invention, its use in the full area of a projection chip and itssubsequent projection using a digital cinema projector.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the following description of preferred embodiments, reference is madeto the accompanying drawings that form a part hereof, and in which isshown by way of illustration specific embodiments in which the inventionmay be practiced. It is to be understood that other embodiments may beutilized and structural changes may be made without departing from thescope of the preferred embodiments of the present invention.

Embodiments of the present invention utilize a maximized 16:9 aspectratio image capture area to lower display magnification and imagedegradation due to display magnification, and to reduce the amount ofanamorphic squeeze or stretch during photography to lower imagedegradation due to anamorphosis. The amount of horizontal anamorphicsqueeze (for front anamorphs) or vertical anamorphic stretch (for rearanamorphs) used during filming may be in the ratio of 2.40:1 over 16:9(the ratio of the widescreen display aspect ratio over the image captureaspect ratio or approximately 1.34), or alternatively the amount ofvertical anamorphic squeeze (for front anamorphs) or horizontalanamorphic stretch (for rear anamorphs) in the ratio of 16:9 over 1.33:1(the ratio of the image capture aspect ratio over the standardtelevision display aspect ratio, which is also approximately 1.34) tomaximize the image capture area. Note than an anamorphic squeeze orstretch other than the ratio of the widescreen display aspect ratio overthe image capture aspect ratio, or alternatively the image captureaspect ratio over the standard television display aspect ratio, will notmaximize the image capture area and thus will not maximize overalldisplay image quality.

In film applications, embodiments of the present invention utilize afilm frame that is only three perforations in height to reduce theamount of original film needed. FIG. 3 illustrates an exemplary threeperforation anamorphic film frame produced by an anamorphic imagingsystem according to embodiments of the present invention. In the threeperforation example of FIG. 3, the total available frame area 300 isapproximately 0.980 inches by 0.546 inches, representing an aspect ratioof approximately 1.79:1 and an area available for anamorphic extractionof approximately 0.455 sq. inches, or approximately 80% of thePanavision® 2.40:1 anamorphic projection aperture having an area of0.569 sq. inches. Embodiments of the present invention capture images ina frame 302 contained within the total available frame area 300 andsized to maximize image area. A widescreen image may be captured withinframe 302 using an anamorphic lens with a horizontal squeeze ratio ofapproximately 1.34, chosen to horizontally squeeze the widescreen imagewhile maximizing the image capture area. In addition, a widescreen imagemay be captured using a rear anamorphic lens with a vertical stretchratio of approximately 1.34, chosen to vertically stretch the widescreenimage to the size of the frame, as described in related U.S. Utilityapplication Ser. No. 10/923,289 entitled “Anamorphic Imaging System.”Alternatively, a standard television image may be captured within frame302 using an anamorphic lens with a vertical squeeze ratio ofapproximately 1.34, chosen to vertically squeeze the standard televisionimage while maximizing the image capture area. In addition, the standardtelevision image may be captured using a rear anamorphic lens with ahorizontal stretch ratio of approximately 1.34, chosen to horizontallystretch the standard television image to the size of the frame, asdescribed in related U.S. Utility application Ser. No. 10/923,289entitled “Anamorphic Imaging System.” Note that the same anamorphic lenswith a 1.34 squeeze or stretch ratio, rotated 90 degrees, may beutilized to capture both formats on the same image capture area.

The frame 302 according to embodiments of the present invention ispreferably not chosen to be as wide or as tall as the available framearea 300 to avoid having the frame too close to the perforations or theadjacent frame.

Additionally, the frame 302 may be sized in consideration of digitalimagers used for cine applications. Digital imagers may be employed forcapturing images for standard television, digital television and motionpictures. The digital standard for high definition television (HDTV)specifies an aspect ratio of 16:9 (1.78:1). Because of the HDTVstandard, digital imagers may be designed to have an aspect ratio ofapproximately 16:9. In addition, because digital imagers may be used forcine applications as well, digital imagers can be designed with a sizethat approximates the area of three-perforation film as described above.FIG. 4 illustrates a digital imager 400 capable of capturing a 16:9image 400 for HDTV or a Super 35 frame 402 for cine applications (seereference character 200 in FIG. 2). Note, however, that if image area402 is used to capture a motion picture frame, approximately 30% of thetotal imaging area 400 will be unused. If, for example, the digitalimager 400 is 1920 pixels wide by 1080 pixels high, the number of activehorizontal lines used in image area 402 may be only 800 instead of 1080,and the remainder of the lines will be wasted. As with original Super 35film, the Super 35 digital frame 402 must be converted to the releaseprint format of FIG. 1, and because the image area is small, imagedegradation will occur when during magnification. Thus, as with film,embodiments of the present invention seek to maximize the active area ofdigital imager 400 by capturing a widescreen image using an anamorphiclens with a horizontal squeeze or vertical stretch of approximately1.34, or by capturing a standard television image using an anamorphiclens with a vertical squeeze or horizontal stretch of approximately1.34.

Preferred embodiments of the present invention therefore employ an imagecapture area with dimensions selected in consideration of multiplefactors, some applicable to both film and digital applications, and somespecific to either film or digital applications. The image capture areais selected to maximize the image area to reduce projectionmagnification and image degradation due to projection magnification, andreduce the amount of anamorphic squeeze or stretch during filming tolower image degradation due to anamorphosis. Use of a single imagecapture area also enables the same anamorphic lenses to be used foreither film or digital capture. The image capture area is furtherselected to be only three perforations in height to reduce the amount oforiginal film needed for film applications, and to fit within themaximum three perforation high image area of approximately 0.980 inchesby 0.546 inches. The image capture area is still further selected tohave an aspect ratio of 16:9 for HDTV, and to fit within the totalimaging area of a digital imager of approximately 0.945 inches by 0.532inches.

The image capture area of preferred embodiments of the present inventionis illustrated in FIG. 3 as film area 302 (film applications), andillustrated in FIG. 4 as imaging area 404 (digital applications). Ineither application, the image capture area is approximately 0.900 incheswide by approximately 0.506 inches tall, providing an aspect ratio ofapproximately 16:9. The image capture area fits within both the maximumthree perforation film frame 300 of FIG. 3 and the total imaging area400 of FIG. 4. Note that in the film embodiment of FIG. 3, the area atthe left of the film frame which is typically reserved for the opticalsoundtrack is not preserved, and instead the entire width of thenegative is used, enabling a larger area to be captured on the film.

For both film and digital cine applications, a widescreen image may becaptured using the same anamorphic lens having a 1.34:1 horizontalsqueeze or vertical stretch, which is less than the 2:1 horizontalsqueeze of the Panavision® anamorphic format. The reduced degree ofanamorphosis combined with using practically the entire area of thethree perforation film frame 300 or total imaging area 400 (which meansless magnification during projection) results in a screen image qualitythat is at least equivalent, and potentially superior to, thePanavision® anamorphic format, while still providing an approximate 25%film cost savings over the conventional four perforation format. Inparticular, because only an approximate 1.34:1 powered anamorphic lensis needed to horizontally squeeze or vertically stretch the image duringfilming, less degradation occurs during filming as compared to thePanavision® anamorphic format which uses an anamorphic lens having apower of 2× in taking. In addition, for standard televisionapplications, a standard television image may be captured using ananamorphic lens having a 1.34:1 vertical squeeze or horizontal stretch.It should be noted that the same anamorphic lens used to produce a1.34:1 horizontal squeeze or stretch may be rotated 90 degrees toproduce a 1.34 vertical squeeze or stretch.

In cine applications, once images are captured either on original filmor digitally according to the image capture area of embodiments of thepresent invention, the image must still be converted to release printfilm. As described above, most existing conventional projection systemsuse a projector that (1) pulls down four perforations per frame, (2)requires that the optical soundtrack be recorded along the entirety ofthe left edge of the film frame, and (3) utilizes an anamorphicprojection attachment having a 2:1 power to unsqueeze the image. To becompatible with conventional projection systems, release prints must betherefore be formatted as in FIG. 1 if they are to be projected in theconventional 2.40:1 widescreen format. As described above, theconversion of original film to release print film in the format of FIG.1 has historically been performed on an optical bench, resulting inimage degradation. However, embodiments of the present invention utilizeknown digital processing techniques implemented by digital imageprocessors to perform the conversion, which avoids the use of optics andthe additional degradation that would occur.

In one exemplary embodiment of the present invention illustrated in FIG.5, the image on the original film 500 is digitally squeezedhorizontally, producing intermediate image 502, and then digitallyresampled (while maintaining the aspect ratio of the intermediate image502) to produce the final or release print image 504. In the exemplaryembodiment of FIG. 5, the original image is squeezed by about 49% in thehorizontal direction, and the intermediate image is then resampled suchthat the resulting film print has the format of FIG. 1. However itshould be understood that dimensions and percentages listed herein areonly exemplary, and that other dimensions and percentages may beemployed according to embodiments of the present invention.

Alternatively, in another exemplary embodiment of the present inventionillustrated in FIG. 6, the image on the original film 600 is digitallystretched vertically, producing intermediate image 602, and thendigitally resampled such that the resulting film print has the format ofFIG. 1 (while maintaining the aspect ratio of the intermediate image602) to produce the final or release print image 604. In the exemplaryembodiment of FIG. 6, the original image is stretched by about 49% inthe vertical direction, and the intermediate image is then resampled togive the format of FIG. 1. It should again be understood that dimensionsand percentages listed herein are only exemplary, and that otherdimensions and percentages may be employed according to embodiments ofthe present invention. Similar digital processes may be used to convert16:9 images from a digital imager to the release print film 504 of FIG.5 or release print film 604 of FIG. 6.

In another embodiment of the present invention illustrated in FIG. 7, awidescreen image 708 (including a reference square 706 two units wideand two units tall) is captured on a digital detector 700 sizedaccording to embodiments of the present invention (i.e., having anaspect ratio of about 16:9). Note that due to the 1.34× horizontalsqueeze, square 706 has a width of only 1.49 units. The capturedwidescreen image 708 may be digitally magnified or minified as needed,but without further stretching or squeezing, to produce converted image714, which fits into the display area of projection chip 702 (having anaspect ratio of about 1.9:1) in state of the art digital cinemaprojectors. In this embodiment, a minimal amount of the width of theprojection chip (see areas designated by reference character 704) willnot be used. Note that FIG. 7 includes dimensions in arbitrary units,which are provided to indicate aspect ratios only, and are not intendedto represent actual sizes. An anamorphic projection attachment with a1.34:1 horizontal unsqueeze 710 may then be used to project the 1.78:1aspect ratio captured widescreen image 714 and produce the final 2.40:1projected image 712. Alternatively, as illustrated in FIG. 8, thecaptured widescreen image 808 may be converted using digital processingtechniques (magnifying, minifying, stretching or squeezing as needed)implemented by digital image processors to produce converted image 814,which precisely fit the 1.9:1 aspect ratio projection chip 802. Ananamorphic projection attachment with a 1.26:1 horizontal unsqueeze 810may then be used to project the 1.9:1 aspect ratio digital image 814 andproduce the final 2.40:1 projected image 812. Note that digital cinemaprojectors with other aspect ratios may also be supported simply bychanging the digital processing and anamorphic projection of thecaptured image.

In another embodiment of the present invention, a widescreen imagecaptured on a digital detector sized according to embodiments of thepresent invention may be digitally stretched horizontally by about 34%or digitally squeezed vertically by about 34% to restore the 2.40:1aspect ratio, then digitally processed as needed for use in digitalapplications (digital television, LCD screens on cameras and camcorders,etc.).

In another embodiment of the present invention illustrated in FIG. 9, astandard television image 908 (including a reference square 906 twounits wide and two units tall) is captured on a digital detector 900sized according to embodiments of the present invention (i.e., having anaspect ratio of about 16:9). Note that due to the 1.34× verticalsqueeze, square 906 has a height of only 1.49 units. The capturedwidescreen image 908 may be digitally magnified or minified as needed,but without further stretching or squeezing, to produce converted image914, which fits into the display area of projection chip 902 (having anaspect ratio of about 1.9:1) in some state of the art digital cinemaprojectors. In this embodiment, a minimal amount of the width of theprojection chip (see areas designated by reference character 904) willnot be used. Note that FIG. 9 includes dimensions in arbitrary units,which are provided to indicate aspect ratios only, and are not intendedto represent actual sizes. An anamorphic projection attachment with a1.34:1 vertical unsqueeze 910 may then be used to project the 1.78:1aspect ratio captured standard television image 914 and produce thefinal 4:3 projected image 912. Alternatively, as illustrated in FIG. 10,the captured standard television image 1008 may be converted usingdigital processing techniques (magnifying, minifying, stretching orsqueezing as needed) implemented by digital image processors to produceconverted image 1014, which precisely fit the 1.9:1 aspect ratioprojection chip 1002. An anamorphic projection attachment with a 1.43:1horizontal unsqueeze 1010 may then be used to project the 1.9:1 aspectratio digital image and produce the final 4:3 projected image 1012. Notethat digital cinema projectors with other aspect ratios may also besupported simply by changing the digital processing and anamorphicprojection of the captured image.

In another embodiment of the present invention, a standard televisionimage captured on a digital detector may be digitally stretchedvertically by about 34% or digitally squeezed horizontally by about 34%to restore the 4:3 aspect ratio, then digitally processed as needed foruse in digital applications (digital television, LCD screens on camerasand camcorders, etc.).

Although the present invention has been fully described in connectionwith embodiments thereof with reference to the accompanying drawings, itis to be noted that various changes and modifications will becomeapparent to those skilled in the art. Such changes and modifications areto be understood as being included within the scope of the presentinvention as defined by the appended claims.

1. A method for capturing a standard television image during originalphotography when an image capture aspect ratio differs from a displayaspect ratio such that an image quality of the image is maximized,comprising: choosing an anamorphic ratio of a taking lens duringoriginal photography to be approximately the image capture aspect ratiodivided by the display aspect ratio; vertically squeezing orhorizontally stretching the standard television image using the takinglens; and capturing the image in a frame sized to utilize as much of atotal available frame area as possible; wherein the image capture aspectratio is selected to be equivalent to a 16:9 aspect ratio of a digitalimager.
 2. The method as recited in claim 1, the total available framearea having a height equivalent to not more than the height of threeperforations in film having regular perforations on a left and rightside of the film and a width equivalent to not more than a distancebetween the perforations on the left and right side of the film.
 3. Themethod as recited in claim 2, further comprising choosing the anamorphicratio to be approximately 1.34:1.
 4. The method as recited in claim 1,further comprising selecting the anamorphic ratio and sizing the frameto provide an image capture area of approximately 0.900 inches wide byapproximately 0.506 inches tall.
 5. A method for generating a digitalimage suitable for display in a digital cinema projector from imagescaptured according to the method of claim 1, the digital cinemaprojector including a projection chip having a display area, the methodcomprising: magnifying or minifying the captured image as needed usingdigital processing techniques to produce a digital image that utilizesas much of the total availablearea of the display area as possible.
 6. Amethod for generating a digital image suitable for display in a digitalcinema projector from images captured according to the method of claim1, the digital cinema projector including a projection chip having adisplay area, the method comprising: magnifying, minifying, stretchingor squeezing the captured image as needed using digital processingtechniques to produce a digital image that utilizes the entire displayarea.
 7. A method for generating a digital image suitable for display ina digital application from images captured according to the method ofclaim 1, the method comprising: vertically stretching the captured imageby about 34% to produce an intermediate image; and magnifying orminifying the intermediate image as needed using digital processingtechniques to produce a digital image suitable for the digitalapplication.
 8. A method for generating a digital image suitable fordisplay in a digital application from images captured according to themethod of claim 1, the method comprising: horizontally squeezing thecaptured image by about 34% to produce an intermediate image; andmagnifying or minifying the intermediate image as needed using digitalprocessing techniques to produce a digital image suitable for thedigital application.
 9. An anamorphic imaging system for capturing astandard television image, comprising: a detector for capturing thestandard television image; and an anamorphic lens for verticallysqueezing or horizontally stretching the standard television image intoan image capture area that fits within the detector; wherein theanamorphic lens has a vertical squeeze or horizontal stretch ratiochosen to maximize the image capture area and image quality by utilizingas much of the detector as possible while maintaining an aspect ratio ofabout 16:9.
 10. The anamorphic imaging system as recited in claim 9, thedetector having a height equivalent to not more than the height of threeperforations in film having regular perforations on a left and rightside of the film and a width equivalent to not more than a distancebetween the perforations on the left and right side of the film.
 11. Theanamorphic imaging system as recited in claim 9, wherein the anamorphiclens has a vertical squeeze or horizontal stretch of approximately1.34:1.
 12. The anamorphic imaging system as recited in claim 9, whereinthe anamorphic lens has a vertical squeeze or horizontal stretchselected to enable the image capture area to fit within the dimensionsof a digital imager.
 13. The anamorphic imaging system of claim 9,further comprising: a digital image processor for generating a digitalimage from the captured standard television image, the digital imagesuitable for display in a digital cinema projector including aprojection chip having a display area, the digital image processorprogrammed for magnifying or minifying the captured image as neededusing digital processing techniques to produce a digital image thatutilizes as much of the display area as possible.
 14. The anamorphicimaging system of claim 9, further comprising: a digital image processorfor generating a digital image from the captured standard televisionimage, the digital image suitable for display in a digital cinemaprojector including a projection chip having a display area, the digitalimage processor programmed for magnifying, minifying, stretching orsqueezing the captured image as needed using digital processingtechniques to produce a digital image that utilizes the entire displayarea.
 15. The anamorphic imaging system of claim 9, further comprising:a digital image processor for generating a digital image from thecaptured standard television image, the digital image suitable fordisplay in a digital application, the digital image processor programmedfor vertically stretching the captured image by about 34% to produce anintermediate image, and magnifying or minifying the intermediate imageas needed using digital processing techniques to produce a digital imagesuitable for the digital application.
 16. The anamorphic imaging systemof claim 9, further comprising: a digital image processor for generatinga digital image from the captured standard television image, the digitalimage suitable for display in a digital application, the digital imageprocessor programmed for horizontally squeezing the captured image byabout 34% to produce an intermediate image, and magnifying or minifyingthe intermediate image as needed using digital processing techniques toproduce a digital image suitable for the digital application.
 17. Amethod for capturing a widescreen image during original photography whenan image capture aspect ratio differs from a display aspect ratio suchthat an image quality of the image is maximized, and generating arelease print image from the captured widescreen image, comprising:choosing an anamorphic ratio of a taking lens during originalphotography to be approximately the display aspect ratio divided by theimage capture aspect ratio; capturing the image in a frame sized toutilize as much of a total available frame area as possible; verticallystretching or horizontally squeezing the captured image utilizingdigital processing techniques to produce an intermediate image; andresampling the intermediate image both horizontally and vertically usingdigital processing techniques to generate the release print image;wherein the image capture aspect ratio is selected to be equivalent to a16:9 aspect ratio of a digital imager.
 18. The method as recited inclaim 17, further comprising: stretching the captured image by about 49%in a vertical direction to produce the intermediate image; andresampling the intermediate image by about 9.3% in both the horizontaland vertical directions.
 19. The method as recited in claim 17, furthercomprising: squeezing the image by about 49% in the horizontal directionto produce the intermediate image; and resampling the intermediate imageby about 36.4% in both the horizontal and vertical directions.